This invention concerns window guards for preventing entry into a building through the window.
Such guards are in widespread use and typically consist of a welded frame work of steel bars securely fastened over the outside of the window opening. While effective against intruders, these structures create a potential hazard as they prevent a quick exit through the window in fire emergencies.
Latching mechanisms have been devised to allow quick release of the window guard, as for example the mechanism shown in U.S. Pat. No. 4,634,157, where a single latch is operable by a door knob located on the inside wall next to the window to release a locking engagement to a pin fixed within a hollow member of the window guard framework.
A single latching point renders the structure vulnerable to being overcome with a pry bar. Multiple latches would be slow to release in an emergency. The cam mechanism shown would make it difficult to install the guard framework as it requires manipulation of the door knob by someone inside as another person positions the window guard framework over the window from the outside. Careful alignment of the mating parts is also necessary.
It is the object of the present invention to provide a window guard with a quick release latching system able to release latching at multiple points by operation of a single operator handle.
It is another object to provide such a window guard which allows easy installation of the window guard framework from the outside of the building without requiring help from a person on the inside.
These and other objects of the invention which will become apparent upon a reading of the follow specification and claims are achieved by a latching mechanism comprised of an elongated latching member slidable within a hollow shield member forming a portion of the window guard framework. The latching member is spring loaded to be urged towards a rotatable elongated cam rod extending through the building wall and into the hollow member. The cam rod has a slot in one end which is aligned with an edge at one end of the slidable latching member, and is engagable with the edge to thereby latch the window guard framework by engagement with the latching member.
The cam rod is restrained against axial movement by spaced collars on either end, but may be rotated with a handle on the inside of the building to cam the locking member opening edge wall out of the slot in the cam rod, releasing the framework to allow it to be pushed away from the window.
One or more fixed latching posts spaced from the cam rod each have a slot arranged to be engaged or disengaged with the locking member simultaneously with the engagement/disengagement of the latching member edge with the cam rod by sliding movement of the latching member so that the framework can be latched at multiple locations defined by the fixed pins and cam rod, all locations released by rotation of the single cam rod.